This invention relates to a polyimide adhesive that is useful in bonding integrated circuit chips to a lead frame, where the leads are subsequently soldered. In particular, it relates to a solution of a polyimide made from a dianhydride and a mixture consisting essentially of an aromatic diamine and an aliphatic diamine.
In manufacturing microelectronic components, integrated circuit chips are bonded to lead frames using a polyimide resin. Later, the leads from the chips are soldered to the leads from the lead frames. A persistent problem in the industry has been the failure of the solder to "wet" the leads and form a good electrical connection.